“The cause of hypertension in insomniacs is due to the number of times the individual wakes during the night as well as their sleep latency – the length of time it takes to accomplish the transition from full wakefulness to sleep,” says Christopher Drake, associate scientist at the Henry Ford Hospital Sleep Disorders and Research Center and lead author of this study.

“We found that the longer it took the subjects to fall asleep and more times they woke during the night, the more severe their hypertension.”

The study will be presented Tuesday, June 12 at the Sleep 2012 Conference in Boston.

Insomnia is the inability to fall asleep or remain asleep and is the most common sleep complaint among Americans. According to the National Center for Sleep Disorders Research at the National Institutes of Health, about 30 to 40 percent of adults say they have some symptoms of insomnia within a given year, and about 10 to 15 percent of adults say they have chronic insomnia.

The Henry Ford study compared 5314 subjects with insomnia to those with normal sleep habits using an internet-based questionnaire. The questionnaire looked for patterns of insomnia symptoms, presence and severity of hypertension and sleep and health habits. The normal sleepers were then compared to insomniacs for prevalence of hypertension.